class Student():
    count=0
    def __init__(self,name):
        self.name=name
        Student.count+=1

if Student.count!=0:
    print("测试失败！")
else:
    A=Student('A')
    if Student.count!=1:
        print('测试失败！')
    else:
        B=Student('B')
        if Student.count!=2:
            print("测试失败！")
        else:
            print("Students:",Student.count)
            print("测试通过！")

